Cap for a container neck

ABSTRACT

A cap for a container neck includes a tubular skirt defining a longitudinal central axis, and a plurality of longitudinal ribs distributed around a periphery of the skirt, each having a free supporting end for the pad of at least one finger of a user. The plurality of ribs on the skirt includes main ribs and secondary ribs, the supporting ends of the main ribs having a radius of curvature greater than a radius of curvature of the supporting ends of the secondary ribs. At least one of the secondary ribs is arranged between the main ribs. A tamperproofing strip, centered on the axis, is connected to the skirt by a weakening line designed to break when the cap is first opened. The tamperproofing strip includes longitudinal ribs distributed around the outer periphery of the strip, each with a free supporting end for the pad of at least one finger.

The present invention relates to a cap for a container neck.

The invention generally pertains to caps capable of covering the neck of a container. In a known manner, the lateral surface of the cap includes a raised portion so as to facilitate the manipulation of the cap by a user wishing to open or close a container, by screwing and unscrewing. The fingers of the user, and in particular the thumb, exert a force on the cap so as to rotate it around the neck.

Different solutions exist to facilitate the opening or improve comfort during opening, but they are not satisfactory. Arranging completely pointed ribs provides good grip, but aggressive contact, which may hurt the fingers. Arranging all rounded ribs is pleasant to the touch, but the fingers slide too much.

Alternatively, it has been considered to implement a bi-injection molding method so as to combine the properties of different materials. The outer profile can be made from an elastomer, and the inner portion with a polymer material traditionally used to manufacture the caps. The cap obtained is, however, more expensive and difficult to recycle.

EP-A-1 914 174, on which the preamble of claim 1 is based, describes a cap for a container neck, comprising a tubular skirt coaxially surrounding the neck and outwardly provided with a plurality of longitudinal ribs. The cap of EP-A-1 914 174 also comprises an outwardly smooth tamperproofing strip.

The aim of the present invention is to propose a cap that, while being cost-effective, can be manipulated effectively and comfortably.

To that end, the invention relates to a cap as defined in claim 1.

The invention thus makes it possible to obtain a good compromise between, on the one hand, the feeling of comfort owing to the main ribs whereof the supporting end has a large curve radius and, on the other hand, the effectiveness of the grip and the transmission of force owing to the secondary ribs, whereof the supporting end has a small curve radius. Furthermore, the ribs arranged on the tamperproofing strip further improve the feeling of comfort during opening. Moreover, in particular for a very small cap, the user has the sensation of manipulating a larger cap.

Other advantageous features of the invention, considered alone or in combination, are specified in claims 2 to 11.

The invention will be better understood upon reading the following description, provided solely as a non-limiting example and done in reference to the drawings, in which:

FIG. 1 is a perspective view of a cap according to the invention,

FIG. 2 is an elevation view of the cap of FIG. 1,

FIG. 3 is a longitudinal cross-sectional view of the cap of FIG. 1,

FIG. 4 is a larger scale view of the circled area IV of FIG. 3,

FIG. 5 is a partial cross-section along line V-V of FIG. 3,

FIGS. 6, 7 and 8 are views similar to FIG. 5, respectively showing alternative embodiments according to the invention, and

FIGS. 9 and 10 are a perspective view and a longitudinal cross-sectional view, respectively, of a cap according to another alternative embodiment according to the invention.

FIGS. 1 to 5 show a cap 1 for a container neck, the latter not being shown. The cap 1 is a tubular piece centered on an axis X-X that defines the longitudinal direction thereof. The cap 1 has an axial symmetry, with the exception of its inner thread 8, visible in FIGS. 3 and 4, which allows the screwing and unscrewing of the cap 1 around the container neck. Commonly, the cap 1 is obtained by molding with a polymer material. In particular, the cap 1 can be made by polyethylene injection.

The cap 1 comprises a substantially planar transverse upper wall 2, which, outwardly, is slightly raised on the periphery, as shown in FIG. 1. The lateral wall of the cap 1 is tubular with axis X-X, and comprises two main portions, i.e. a skirt 3 and a strip 4. The angle between the transverse wall 2 and the skirt 3 assumes a rounded shape. The lateral wall of the cap 1 also comprises an overthickness 6, which corresponds to a variation of the inner and outer diameter of the skirt 3 at the axial level where the latter is connected to the strip, and a peripheral border 7, which forms the end opposite the transverse wall 2.

In practice, the strip 4 and the skirt 3 are initially connected by a weakening line, not shown, adapted to break the first time the cap 1 is opened. The weakening line is situated axially substantially at the overthickness 6. In this way, the skirt 3 is removable in relation to the neck of the container, whereas the strip 4 is intended to remain around the neck after the first time the cap 1 is opened, and for that reason is commonly called a tamperproofing strip. The weakening line serves as a control for that first opening, intended for users. More specifically, the inner thread 8 allows the screwing and unscrewing of the skirt 3, which coaxially surrounds the neck of the container. For the strip 4 to be able to remain on the neck after opening, its inner surface is provided with bulges 9. The bulges 9 extend radially protruding toward the inside of the cap 1 from the inner surface of the strip 4, situated globally in a same transverse plane, while being distributed all around the inner periphery of the strip 4. When the cap 1 is assembled to the neck, the bulges 9 extend axially below a boss of the neck. The bulges 9 are adapted, when the cap is lifted for the first time, to abut axially against that boss.

The skirt 3 is provided with a plurality of main 31 and secondary 32 longitudinal ribs, distributed along its outer periphery, that extend between the transverse wall 2 and the overthickness 6. As shown in FIGS. 3 and 5, each rib 31, 32 is provided with a free supporting end 331, 332 for the pad of a finger D of the user. As visible in FIG. 5, the supporting ends 331 of the main ribs 31 have, in cross-section transverse to axis X-X, a larger curve radius R than the curve radius r of the supporting ends 332 of the secondary ribs 32. Furthermore, the main ribs 31 and the secondary ribs 32 follow one another along the periphery of the skirt 3, so that when the pad of the finger D of the user is pressed against the supporting end 332 of the secondary ribs 32, that pad also bears against the supporting ends 331 of two peripheral ribs 31 situated, along the periphery of the skirt, on either side of that secondary rib 32.

The strip 4 is also provided with a plurality of main 41 and secondary 42 longitudinal ribs distributed along its outer periphery, which extend partially between the overthickness 6 and the border 7. Like those of the skirt 3, the primary ribs 41 and the secondary ribs 42 follow one another along the outer periphery of the strip 4, each being provided with a free supporting end 441 and 442 for the pad of a finger D of the user. The supporting ends 441 of the main ribs 41 have, in cross-section transverse to the axis X-X, a larger curve radius than the curve radius of the supporting ends 442 of the secondary ribs 42.

In this way, the skirt 3 and the strip 4 are respectively provided with two types of ribs that follow one another on their outer periphery: the main ribs 31 and 41 on the one hand, and the secondary ribs 32 and 42 on the other hand. Comparatively, the ribs 31 and 41 can be qualified as thick and rounded, while the ribs 32 and 42 assume a fine and pointed shape. In the embodiment considered here, the ribs of the skirt 31 and 32 and the ribs of the strip 41 and 42 are axially aligned with one another, matching by type: 31 with 41, 32 with 42.

Each rib 31, 32, 41, 42 has dimensions that can be defined as its length, thickness, and width:

the length is the dimension in the longitudinal direction, substantially parallel to the axis X-X of the cap 1,

the thickness is the protruding dimension of the rib, in relation to the cylindrical surface of the skirt 3 or the strip 4, oriented toward the outside of the cap 1 in a direction radial to the axis X-X,

the width is the orthoradial dimension of the base of the rib, in the region where it forms a projection with the cylindrical surface of the skirt 3 or of the strip 4.

In the embodiment considered in FIGS. 1 to 5, the ribs 31 and 32 of the skirt 3 each have a base with a substantially constant width B31 or B32 from one longitudinal end of the rib to the other, while the ribs 41 and 42 of the strip for each have a base with a variable width B41 or B42, more specifically which increases along the rib toward the border 7, as shown in FIG. 2.

Furthermore, the thickness E31 or E32 of the ribs 31 or 32 of the skirt 3 is substantially constant over the entire running portion 31 a or 32 a of the rib, including at its longitudinal end 31 c or 32 c connecting to the overthickness 6, while its ends 31 b or 32 b turned toward the transverse wall 2 are flared between the circumferences C1 and C0 of the cap, at the axial level of which the thickness of the rib is respectively maximal and zero.

The thickness E41 or E42 of the ribs 41 or 42 of the strip 4 increases from the longitudinal end 41 b and 42 b of the ribs, turned toward the skirt 3, to reach a maximum at their longitudinal end 41 c and 41 c, over a circumference C2 situated at the axial end of the strip 4 opposite the transverse wall 2 of the cap 1, i.e. at the border 7.

As visible in FIG. 5, when the cap 1 is opened, the pad of the fingers of the user are positioned, on the skirt 3, on at least two ribs 31, which procures a sensation of comfort, and, as a result, on at least the rib 32 situated peripherally between the two aforementioned ribs 31, which allows a good grip of the cap. More generally, the first time the cap is opened, i.e. before the aforementioned weakening line is broken, the fingers touch both the ribs 31 and 41 and the ribs 32 and 42, but not excessively, in particular when, as considered in FIG. 5, said ribs 32 and 42 are as thick as the ribs 31 and 41, which amounts to saying that the thicknesses E31 and E32 are equal. In this way, the ribs 32 and 42 cannot penetrate too deeply into the pad of the fingers, but have sufficient dimensions to ensure a good grip. Furthermore, the ribs 32 and 42 are advantageously sized, in particular regarding their width B32 and B42, to have a bending deformation capacity in a direction orthoradial to the axis X-X. In this way, the flexibility resulting from the fineness of said secondary ribs 32 and 42 participates in the feeling of comfort, giving the user the impression of a feeling close to that he might perceive in contact with an elastomeric surface.

In order to produce the expected effects, the main ribs 31 and 41 and the secondary ribs 32 and 42, respectively, have a particular profile, adapted to their function, as shown in FIG. 5 for the ribs 31 and 32 of the skirt 3. In practice, in the embodiment considered here, the main ribs 31 and 41 have, in cross-section transverse to the axis X-X, an arc of circle profile having radius R, which makes it possible to obtain a comfortable sensation to the touch. The secondary ribs 32 and 42 have, in cross-section transverse to the axis X-X, a base in the shape of a truncated isosceles triangle, the truncated apical angle of which is comprised between 30 and 45°, with their supporting ends 432 and 442 having an arc of circle profile with curve radius r.

In practice, the finger D is capable of bearing on the portions of the ribs of the skirt 3 and the strip 4 having a maximal thickness. This corresponds in particular on the one hand to the circumference C1 on the skirt 3, and on the other hand to the circumference C2 on the strip 4. In this way, the ribs of the skirt 31 and 32 and the ribs of the strip 41 and 42 jointly define a global enclosure E between C1 and C2, having a tapered shape, centered on the axis X-X and converging toward the wall: this enclosure E thus at least partially fits the pad of the finger D of the user, as visible in FIG. 3.

FIGS. 6, 7 and 8 show other embodiments of the main 31 and secondary 32 ribs of the skirt 3, which can be broken down for the main 41 and secondary 42 ribs of the strip 4.

In FIG. 6, the thickness E31 of the main ribs 31 is smaller than the thickness E32′ of the secondary ribs 32′. The engagement of the pad of the finger D on the secondary rib 32′ is thus more pronounced, but the feeling of comfort is lesser.

In FIG. 7, the thickness E31 of the primary ribs 31 is larger than the thickness E32″ of the secondary ribs 32″. The engagement of the pad of the finger D on the secondary rib 32″ is thus less pronounced, but the feeling of comfort is better.

In FIG. 8, two of the secondary ribs 32″′ are arranged in the intermediate peripheral space between two of the main ribs 31. The engagement of the pad of the finger D on the secondary ribs 32″′ is thus facilitated by the double bearing, but the feeling of comfort may be lessened.

FIGS. 9 and 10 show another embodiment of the cap 1, in which, compared with the embodiment of the preceding figures, the difference in diameter between the skirt 3 and the strip 4 is greater: at the overthickness 6, the cap 1 has a significant inner and outer diameter variation, with the result that, in the example of FIGS. 9 and 10, the outer diameter of the skirt 3 is smaller than the inner diameter of the strip 4. This difference in diameter is used so that the end 131 c of the main ribs 131 of the skirt, which is turned toward the strip 4, increases following a concave profile adapted to the profile of the pad of the fingers D of the user. The running portion 131 a and the other end 131 b of these ribs 131 are similar to the portion 31 a of the end 31 b of the ribs 31 described above. Likewise, the secondary ribs 132 of the skirt are similar to the ribs 32 described above.

The embodiment of FIGS. 9 and 10 differs from the embodiment of the preceding figures also in that its band is provided with ribs 140 that are all identical to each other. In other words, it is not possible here to differentiate between main and secondary ribs of the strip 4. That being the case, said ribs 140 are advantageously individually sized according to the same considerations as the ribs 41 and 42 previously described. In particular, in the embodiment shown in FIGS. 9 and 10, the ribs 140 have an increasing thickness E140, like that of the ribs 41 and 42, and jointly define, with the ribs 131 and 132 of the skirt 3, the globally tapered enclosure E mentioned above.

Other embodiments can be considered, while remaining within the scope of the invention. The main point for the ribbed cap is to provide a good compromise between the feeling of comfort and effective gripping when the pad of the finger of the user engages on the cap. This advantage is still more pronounced when the cap is small, short and light. The ribs can be implemented on all existing caps and closing devices for containers, without adding weight, simply by modifying the usual molds. Also, the usual raw material is still preferably used for an assembly of different materials, which thus makes it possible to preserve the usual properties of the cap, including good recyclability.

Irrespective of the embodiment, in order to improve the feeling of comfort during opening, the cap includes the strip also provided with ribs, either identical to one another, as for the ribs 140 of FIGS. 9 and 10, or differentiated into main and secondary ribs meeting the definition given above, as for the main ribs 31 and secondary ribs 32, 32′, 32″ and 32″′ of FIGS. 1 to 8. In this way, and in particular for much smaller caps, the user has the feeling of manipulating a much larger cap. 

1. A cap for a container neck, comprising: a tubular skirt defining a longitudinal central axis, which is capable of coaxially surrounding the neck and which is outwardly provided with a plurality of longitudinal ribs, distributed along the periphery of the skirt and each provided with a free supporting end for the pad of at least one finger of the user, wherein the plurality of ribs of the skirt includes main ribs and secondary ribs, the supporting ends of the main ribs having, in cross-section transverse to the axis, a curve radius larger than the curve radius of the supporting end of the secondary ribs, wherein, along the periphery of the skirt, at least one of the secondary ribs is arranged between the main ribs so that, when the pad of the finger is pressed against the supporting end of one of the secondary ribs to screw or unscrew the cap, that pad also bears against the supporting ends of two main ribs situated on either side of said secondary rib, and wherein the cap also comprises a tamperproof strip centered on the axis, connected to the skirt by a weakening line adapted to break the first time the cap is opened, wherein the tamperproofing strip is outwardly provided with longitudinal ribs that are distributed along the outer periphery of the strip and each provided with a free supporting end for the pad of at least one finger of the user.
 2. The cap according to claim 1, wherein the secondary ribs of the skirt are flexible in relation to the rest of the skirt, in particular deformable by bending in a direction orthoradial to the axis during bearing of the pad of the finger of the user.
 3. The cap according to claim 1, wherein each main or secondary rib of the skirt has a radial thickness that is substantially constant over the entire running portion of the rib and that is decreasing at least at one of its longitudinal ends.
 4. The cap according to claim 3, wherein, at its longitudinal end turned toward a transverse wall for closing the skirt, each main or secondary rib of the skirt has a radial thickness continuously decreasing between two circumferences of the cap, at the axial level of which that thickness is respectively maximal and zero.
 5. The cap according to claim 3, wherein, at its longitudinal end opposite a transverse wall for closing the skirt, each main or secondary rib of the skirt has a radial thickness that increases in the direction opposite said transverse wall, while in particular having a concave profile.
 6. The cap according to claim 1, wherein the plurality of ribs of the strip includes main ribs and secondary ribs, the supporting ends of said main ribs having, in cross-section transverse to the axis, a larger curve radius than that of the supporting ends of said secondary ribs, and wherein, along the periphery of the strip, at least one of the secondary ribs is arranged between the main ribs such that, when the pad of the finger of the user is pressed against the supporting end of one of the secondary ribs to unscrew the cap for the first time, that pad also bears against the supporting ends of two main ribs situated on either side of the secondary rib.
 7. The cap according to claim 6, wherein before breaking of the weakening line, the angular positioning around the axis of the main ribs of the strip is identical to that of the main ribs of the skirt, and the angular positioning of the secondary ribs of the strip is identical to that of the secondary ribs of the skirt.
 8. The cap according to claim 1, wherein the radial thickness of each rib of the strip increases from its longitudinal end turned toward the skirt at its longitudinal end opposite the skirt, to reach a maximum radial thickness at the axial level of a circumference of the cap, forming a peripheral border.
 9. The cap according to claim 1, wherein the main and secondary ribs of the skirt and the ribs of the strip jointly define a substantially tapered enclosure, centered on the axis and converging toward a transverse wall for closing the skirt, situated axially opposite the strip.
 10. The cap according to claim 6, wherein the radial thickness of each main or secondary rib of the strip increases from its longitudinal end turned toward the skirt at its longitudinal end opposite the skirt, to reach a maximum radial thickness at the axial level of a circumference of the cap, forming a peripheral border.
 11. The cap according to claim 6, wherein the main and secondary ribs of the skirt and the main and secondary ribs of the strip jointly define a substantially tapered enclosure, centered on the axis and converging toward a transverse wall for closing the skirt, situated axially opposite the strip. 